Contact terminal for vacuum tubes



p 7, 1948. 5. KOCH 2,448,808

CONTACT TERMINAL FOR VACUUM TUBES Filed May 2, 1945 M INVENTOR ATTORNEY Patented Sept. 7, 1948 UNITED STATES PATENT OFFICE CONTACT TERMINAL FOR VACUUM TUBES Stanley J. Koch, Clifton, N. J., assignor to Allen B. Du Mont Laboratories, Inc., Passaic, N. J., a corporation of Delaware Application May 2, 1945, Serial No. 591,465

2 Claims. 1

This invention relates to a terminal or contact for making connection from a source of electrical potential to an electrode extending inside of an electron tube or cathode-ray tube and for the process of securing said contact to the wall of said tube.

Heretofore, connections of this type have been made by fusing a portion of the glass wall of the tube and locating the terminal so that a lead could be connected thereto. With such connections the glass tube was in danger of being broken or cracked by the contact being struck or too much pressure being applied thereto. Besides, since the contact surface between the contact member and the wall of the tube was not much more than was provided by the thickness of the wall of the tube, the danger of leaking and breaking the vacuum in the tube was increased.

By the present invention prior difliculties have been overcome and an electrical conatact element is securely and firmly mounted on the tube in such a Way that the danger of the tube being broken by force applied to the contact or a blow striking and breaking it is minimized, and at the same time the danger of leakage of air through the part where the contact is installed in the wall of the tube is materially decreased or entirely overcome.

The invention may be understood in connection with the accompanying drawing; in which:

Fig. 1 is a plan View of the contact;

Fig. 2 is a side view partly in section showing the contact and a pin therefor, which pin has a short cylinder of glass thereon; and

Fig. 3 is a sectional view showing a portion of the wall of a tube with the contact in place.

In the drawing, reference character I indicates the rounded portion or head of a contact to which connection is to be made from a source of potential. This connection may be made, for example, by a snap terminal which is held on head I in the known way.

Head l extends into a neck portion 2 which is flared outwardly into a disc portion 3 which is turned upwardly as indicated at 4 and ends in a downwardly extending ring portion, the end of which is shown by the reference character 5.

A metal rod 6 is installed in the neck portion 2 of the contact I and fits tightly therein so as to maintain both a mechanical and electrical connection between the contact I and rod 6.

A glass bead 'l is placed on the rod 6 with one end thereof in contact with the portion 3 of the terminal.

A hole or opening slightly larger than the bead l is provided in a wall 8 of the tube where the contact is to be installed. The head 1 and rod 6 are placed in this hole with the disc portion 3 of the contact I in contact with the outer surface of the glass wall. The glass is then fused by applying heat to it and the corresponding portion of the bead 'l to fuse the same together as shown in Fig. 3 and also to fuse the bead 'l more securely on the rod 6, and also fuse the glass so that it flows lightly around the portion 4 of the contact as indicated at 9, thus more securely anchoring the contact in the glass wall and also decreasing the danger of a leakage path forming.

What is claimed is:

1. A metal contact terminal anchored in the wall of a glass tube, which comprises an integral hollow metal head and neck, the lower end of said neck merging into a metal disc the edge of which terminates in an annular inturned flange surrounding said neck, a metal rod tightly fitting in said neck and passing through said wall, and a glass tube integral with said wall fused on said rod on the opposite side of said wall from said head to hold said tube securely on said rod.

2. A metal contact terminal anchored in the wall of a glass tube, which comprises an integral hollow metal head and neck, the lower end of said neck merging into a metal disc the edge of which terminates in an annular inturned flange surrounding said neck, a metal rod tightly fitting in said neck and passing through said wall, a glass tube integral with said wall fused on said rod on the opposite side of said wall from said head to hold said tube securely on said rod, and said inturned flange being also fused to said glass wall and spaced from said neck.

STANLEY J. KOCH.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,738,957 Metcalf Dec. 10, 1929 1,909,797 Anderson, Jr May 16, 1933 1,922,535 Erickson Aug. 15, 1933 2,192,892 Brandt Mar. 12, 1940 2,194,418 Bowie Mar. 19, 1940 2,202,500 Lopp May 28, 1940 2,269,156 Kling Jan. 6, 1942 2,366,459 Rosa Jan. 2, 1945 2,398,535 Koch Apr. 16, 1946 

